Citrix Systems 9.2 Benutzerhandbuch

Classic expressions describe basic characteristics of traffic. In some cases, you 
may want to use the classic expression syntax in an advanced policy. You can do 
so with the advanced expression configuration tool. This can be helpful when 
manually migrating older, classic expressions to the advanced expression format.

Note that when you upgrade the NetScaler to version 9.0 or higher, Integrated 
Caching policies are automatically upgraded to advanced policy format, and the 
expressions in these policies are upgraded to the advanced expression method of 
describing a classic expression. 

The following is the syntax for all advanced expressions that use the classic 
expression syntax:

sys.eval_classic_expr("expression")

The following are examples of classic expressions that you can embed in an 
advanced expression using this syntax:

sys.eval_classic_expr("req.ssl.client.cipher.bits > 1000")

sys.eval_classic_expr("url contains abc")

sys.eval_classic_expr("req.ip.sourceip == 10.102.1.61 -netmask 

255.255.255.255")

sys.eval_classic_expr("time >= *:30:00GMT")

sys.eval_classic_expr("e1 || e2")

sys.eval_classic_expr("req.http.urllen > 50")

sys.eval_classic_expr("dayofweek == wedGMT")

You can configure an advanced expression of up to 1,499 characters in a policy. 
The user interface for advanced expressions depends to some extent on the 
feature for which you are configuring the expression, and on whether you are 
configuring an expression for a policy or for another use.

When configuring expressions on the command line, you delimit the expression 
by using quotation marks (“. . .”or '. . .'). Within an expression, you escape 
additional quotation marks by using a back-slash (\). For example, the following 
are standard methods for escaping quotation marks in an expression:

"\"abc\""

‘\"abc\"’